SMART SENSORS PPT

SMART SENSORS

PRESENTED BYSWARNJEET KAUR

11092011M.TECH ECE

2ND Semester

SENSORS

An electronic device that produces electrical, optical, or digital data derived from a physical condition or event.

SMART SENSORS Smart sensors are sensors with integrated electronics that can perform

one or more of the following function logic functions, two-way communication, make decisions.

Usefulness of Silicon Technology in Smart Sensor

A smart sensor is made with the same technology as integrated circuits.

A smart sensor utilizes the transduction properties of one class of

materials and electronic Smart Sensors properties of silicon (GaAs). A

transduction element either includes thin metal films, zinc oxide and

polymeric films.

Integrated sensors provide significant advantages in terms of overall size

and the ability to use small signals from the transduction element. The IC

industry will get involved in smart sensor if a very large market can be

captured and the production of smart sensor does not require non-

standard processing steps.

Signal conversion effects

TABLE 1: Signal domain with different measurand

Table2-Signal domain with physical effects

Importance and Adoption of Smart Sensor

Cost improvement

Reduced cost of bulk cables and connectors

Remote Diagnostics

Enhancement of application

Self calibration Computation Communication Multisensing System Reliability Better Signal to Noise Ratio

Improvement in characteristics

Non-linearity Cross-sensitivity Offset

General Architecture of smart sensor

Types of Smart Sesnsors

Optical SENSORS Infrared Detector Array Acceleromete Integrated multisensor Bluetooth based smart sensors

WIRELESS SENSOR NETWORK

From the user point of view, querying and tasking are two main services provided

by wireless sensor networks .Queries are used when user requires only the

current value of the observed phenomenon. As wireless sensor networks are data-

centric networks, the user does not query a specific node for the information it

might provide, but defines data (type,location, accuracy, time, etc.) he/she is

interested in and requests it from all nodes that can provide the answer.

Gateway functionality Smart sensor nodes scattered in the field collect data and send it to users

via gateway using multiple hop routes.

Figure 2- Wireless sensor network

The main functions of a gateway are the following

Communication with sensor network - Short-range wireless communication is used

(Bluetooth, UWB, RF, IR, etc.). Provides functions like discovery of smart sensor

nodes, generic methods for sending and receiving data to and from sensors, routing,

etc.

Gateway logic – Controls gateway interfaces and data flow to and from sensor

network. It provides an abstraction level with API that describes the existing sensors

and their characteristics; provides functions for uniform access to sensors regardless of

their type,location or network topology, inject queries and tasks and collect replies.

Communication with users – Gateway communicates with users or other sensor

networks over the Internet,wide area networks (GPRS, UMTS), satellite or some

short-range communication technology.

Communication With Users

Gateway communications with users or other sensor networks over the Internet,

WAN, Satellite or some shortage communication technology.From the user point

of view, quering and tasking are two main services provided by wireless sensor

networks. Queries are used when user requires only the current value of the

observed phenomenon. Tasking is a more complex operation and is used when a

phenomenon has to be observed over a large period of time.Both queries and

tasks of time to the network by the gateway which also collects replies and

forwards them to users.

BlueTooth

Blue tooth operates in the unlicensed ISM band at 2.4 GHZ frequency band and

use frequency hopping spread spectrum technique. A typical Blue tooth device

has a range of about 10 meters and can be extended to 100meters.

Communication channels supports total bandwidth of 1 Mb / sec. A single

connection supports a maximum asymmetric data transfer rate of 721 KBPS

maximum of three channels.

Smart Sensor Node Architecture

Discovery Of The Smart Sensor Nodes

Smart sensor node discovery is the first procedure that is executed upon the gateway

installation. It goals to discover all sensor nodes in the area and to build a list of sensor's

characteristics.

When the gateway is initialized, it performs bluetooth inquiry procedure. When the blue tooth

device is discovered, the major and minor device classes are checked. These parameters are

set by each smart node to define type of the device and type of the attached sensors. Service

class field can be used to give some additional description of offered services. if discovered

device is not smart node it is discarded. Otherwise service database of the discovered smart

node is searched for sensor services.Once connection strings is obtained from the device. Blue

tooth link is established and data exchange with smart mode can start.

CONCLUSION

In conclusion, silicon is very suitable material for fabrication of smart sensors.

But still a lot of research is required to get benefits of the smart sensor but from

the experience of already existing devices, we can expect that in the coming

decade a large number of successful smart sensors will emerge.Bluetooth is a

possible choice for data communication in sensor networks. Good throughput,

low-power and low-cost.

THANKS